Apparatus for measuring power for electrical circuits



Oct.' 6, 1925. 1,555,908

P. H`. BURKHART APPARATUS FOR MEASUHING POWER FOR ELECTRICAL' CIRCUITS Filed Dec. e, l1920 2 sneers-sheet 2 Patented Get. 6, 1925.

ieri..

PAUL H. BURKHART, OF HENRY, ILLINOIS.

APPARATUS FOR MEASURINC- TOWER FOR ELECTRICAL CIRCUITS.

Application led December 8, 1920. Serial No. 429,135.

To all whom t may conce/m.'

Be it known that I, PAUL H. BUnKnAnT, a citizen of the lUnited States, residing at Henry. county of Marshall, State ot lllinois, have invented certain new and useful Improvements `in Apparatus :tor Measuring Power for Electrical Circuits, ot which the following is a speciication.

This invention relates to a method, system, and apparatus used tor measuring at a variable rate the electrical energy consumed in electrical circuits, andhas for its primary object to provide means for varying automatically the operation ot the consumers meters in an electrical distribution circuit in accordance with the amount of power being generated.

lt has been the practice 'for some time to give the consumers whose load characteristics are definitely known favorable rates when they are using power ,at times when the total load on the generating station is small, which heretofore has been accom# plished by using special meters to deter* mine the demand on the consumers circuits at any time, the rate being computed from the individual demand and generating station load data. ln my improved system, the watthour meter in the consumers branch circuit registers energy consumption intermittently, the intervals of registration and nonregistration being variable, and selected by apparatus controlled by the load on the generating station. The quantity registered by the meter in the consumers branch circuit is substantially proportional to the summation of the instantaneous products of the energy consumed, multiplied by a variable factor which at all times depends upon the total load on the system.

More specifically my improved system contemplates the automatic control of operation of a meter by means of electrically operated switches controlled in their positions in accordance with the total load on the generating station. and my prei-'erred form of meter control is by means of circuits periodically and variably interrupted to operate and stop'variably said meter in accordance with said load.

My invention also embodies certain minor details of construction, as hereinafter more definitely will be pointed out and claimed, reference being had to the accompanying i drawings, in which Figure l is a diagrammatic View of one form of my improved system, the same being shown in connection with a single phase system.

Figure 2 is a similar view of my preferred form of mechanism for intermittently interrupting the operation oit the consumers meters, but showing a modified form-ot' control for the auxiliary circuit.

Figure 3 is a detailview of one of the segmented circular disk contact elements showing a method ot adjusting the active periphery or" the disk.

Similar numerals of reference denote corresponding` parts in the several views.

In said drawingsr referring more particularly to Figure 1, the reference numerals 1, 2, denote tA e lines transmitting electrical energy at highpotential `from a suitable generator, not shown, said energy being transmitted to a step-down potential transformer 3, where the line voltage is reduced, and from there is delivered through the lines ll, 5. to the point of consumption or load 6, the energy consumed there being measured by a suitable meter hereinafter to be described.

Inserted in the main transmission line 1, 2, is a current balance ammeter for measuring the total current of the system. lt' desired, a series transformer .or protecting said current balance it'rom high voltage may be inserted, but the same is omitted from the drawings for simplicity. Said current balance comprises sinv coils through whieh the current to be measured flows. Coils 7, 8, 9, 10, are stationary, while the coils 11, 12, are mounted on a frame 13, which is supported on a spindle 14 i'trovided with suitable bearings, the circuit through all of said coils being completed by the conducting strips or wires connecting the same. When a current passes through these coils a magnetic field is established between the same, and a torque is produced, which tends to shift coils 11 and 12 in a counter-clockwise direction, which motion is restrained so that the current produces only a slight deflection. Attached to the under side of the frame 13 is a contact arm 15, adapted to engage con-r tact 16 or contact 17 according to the direction of movement of said frame. When moved counter-clockwise, as above described, contact is made at 16, which completes an electrical circuit through the coil 18 of a motor reversing relay 19, thus closing contacts 20 and 21 and completing an electric circuit through Wires 22, 23, 34; and 3-1 to a suitable motor 2li, thereby causing the latter to rotate in one direction. The rotation ot said motor 2d rotates a screw 25, the speed being reduced by suitable gears 2G and 27, and this rotation moves a switch arin 28 in a clockwise direction. A calibrated helical spring 29 is connected at one end to the underside ot the frame 18, by a screw adjustment 30, and at its other end to the switch arin 28, and is subjected to a definite tension. Then the pull exerted by said spring on the traine 13 equals the force tending to rotate said frame, the two forces will neutralize, and said frame will be restored to its initial position, thus opening contact at l@ and stopping rotation of the motor 24e. The switch arm 28 is left in a position which corresponds to the torce tending to rotate the trame 13, which iii turn is proportional to the square ot the current in the lines l and 2. For every Value of current in said line there is a delinite position for the switch arm 28 when the forces acting upon the frame 18 of the current balance are in equilibrium. When the current in the line l, 2, decreases, the spring 29 will more the traine 13 clochwise through small angle, and contact l? will be closed, completing an electrical ciicuit through the other coil 3l of the motor reversing relay 1.9. vContacts 32 and 38 are thereby closed, thus con -etiiig an electrical circuit to the motor 2l through the lines 22, 28, 34, and 3d, which will cause it to operate in reverse direction, thus moving the switch arm 28 in counter-clockwise direction. The tension on the spring 29 thus gradually is diminished, and when the forces acting on traine 13 again are in equilibriu-fn, said contact l? is opened'the motor stops, and the switch arin 28 is lett in a new position which corresponds to the current jiiowing through the main line l, 2. Thus, whenever the value of the current in th line changes the switch arm 28 will assume a new position corresponding to the line current.

The switch arm 28 is adapted always to establish electrical contact with at least one of a series of contact plates 35 to 43, contact being shown in Figure l as made with plate A second electrical circuit is connected through the switch arm 28, branches oit this circuit being connected to the contact plates 35 to 43, and Voltage from a suitable source is impressed upon the circuit. ln the drawing the primary oi a transformer d4 is connected across the line l, 2, the secondary supplying energy to this second circuit, one lead from said transformer being` connected electrically to the switch arm 28 as shown. Electrical connection is thus established from transformer 44 through arm 28, contact plate 40, a coneach connected with a vevarate contact linger e9 adapted to malte series ot rotating segiiicnted s to 5i', mounted upon a cor hatt 52, said shaft being rotated continuously at constant speed by a c hworlt or other motor 59, the reducing gearing' tor rotating the shatt 58 at suitable speed being chosen for example so as to rotate said shaft at an angular f .0 l ,f e oi no4- F c poen .ii Uire -ma ion a minu e. Y.Jael oi said tingiiers 29 is drawn normally towardsr its disk by a suitable spring 419. and its movement in that direction limited by a stop 42". lt will be observed that the segmented disks increase gradually in angular size from dish 50 to disk 57. so that the contact oi the fingers 49 therewith Varies in proportion the angul size of said disks. The arin is'sliown in contact with plate 40.. which completes the electrical circuit through dish which is ot such a size that contact. made for example tor six tenths ot' the time ot rotation of the sha-ft 58. Said shaft being rotated for example at an angular speed ot one revolution per minute, th@ contact at is made for 36 seconds ot each minute and said contact is broken tor `the other 24 seconds et that minute. The sneed o.; rotation ot the shaft 58 arbitrarily is chosen so that the period of registration d rest of the consumers meters will be small. so that changes in the consumers loads will not atleet the precision ot the measured quantities. llfhen the load on the entire system is at maximum. the switch arm 28 will be held in contactwith plate 4:8, which is connected through lead wire 6l to wire liti, and the auxiliary circuit delivers current to the consumers7 meters without interruption so that energy consumption is registered continuously. lVhen the load on the system is less than the peak load then the arm 28 connects the auxiliary or second circuit through the prop-er segmented circular disk contact. and a lower rate is offered to the consumers. some one of the disks 50 to 5i' interrupting` the circuit through wire 46, thus making and breaking the auxiliary circuit through the transformer e?.

The customers meter shown in Figure l, is an induction type integrating wattliourmeter, which is essentially a split phase induction motor coinprisine' a rotatable ineinber 62, connected to a registering mechanism 63 through a train ot gears, and rotated by the resultant magnetic flux established by the currents flowing in the two coils Gel and 65, the coil 64 being connected across the auxiliary circuit and normally having either a voltage proportional tothe load voltage or zero voltage impressed across it, while the coil 65 is connected in series with the line, and carries a current either equal to or proportional to the current i'lowing` to the load 6. When current i'lows through both coils a rotating magnetic field' is established, which causes the memher 62 of the meter to be rotated.

in a distribution circuit having` a great many metered loads the energy supplied to the potential coils all the consumers meters is considerable, which, with the system shown in Figure l, would require that the rotating' segmented disks and Atheir contact making lingers must be comparatively large, so that they could break the circuit under such conditions. In order to avoid this l have provided a modified construction, shown in Figure 2, for controlling the. make and break ot the auxiliary circuit as follows: rlhe wire i6 leading` from the shaft 5S ca rryinp` current throughone ot the disks 50 to 57, as well as the wire 61 leading from the contact 43, are connected in the circuit with a relay 66, which, when energized, by meansV of its armature 67 closes a control circuit at contact 68, said circuit being` supplied hy wires 69 and 70, from any suitablesource ot power, such as a generator or a storage battery, with the former of which the switch arm 28 may be connected by lead 2Q', and through switch 71, closes a circuit through the auxiliary transformer 47, the current for this circuit being` derived from the transformer 72 in the main line 1, 2, or from some other suitable source. By this arrangement the control current through the wires 69, 70, may be of any desired strength, and the size o'l" the disks 50 to 57 and their cooperating parts yjoverned accordingly.

The operation of my system of measuring` power will be understood as follows: When no current is tlowing through the main line l. 2, the trame 13 will be drawn by the tension ot spring' 29 clockwise, thereby closcontact at 17, energizing` magnet 3l, closingr contacts at 32 and 33 and causing a current to pass through the lines 22, 23, 34 and 34V, to the motor 9A, which will rotate the screw 25 so as to move the switch arm 28 counter-clockwise until the switch arm comes in contact with con-tact 35, in which position the spring 29, which may be properly adjusted by the turnbuckle 78, will cease to be under tension, whereupon the il ce i3 will resume its intermediate position breaking; contact at 17 and stopping the motor 24. Now when an electrical load is put on the system the current passing throuc'h the current balance immediately will (,.use the :traine to move counter-clockwise, closing-zj the circuit at 16, energizing magnet 18, closing the contacts at 2() and 2l,

22, and completing the electrical circuit throi h the wires 23, 34, and 34 to the motor 24, causing the latter to rotate the screw 25 and more the switch arm 28 clock-- wise or downward, so that it will engage successively with contacts 35, 36, etc., this movement of the motor and the switch arm continuing until the tension ot the spring- 29 equals the torque ot the current balanceI` whereupon the trame i3 will assume its intermediate position, brezil-tingv contact at 16 and stormingA the motor 2l. it the ,generator is supplying a maximum load to the systeni the switch arm 28 will move until it engages with contact 4-3, in which position there is a constant flow ot current through the line 6l, and a consequent continuous registration ot energy consumption in the consumers branchesof the distribution circuit. But if the generator supplies a load to the distribution circuit which is less than the maximum, the position ot the switch arm 28 will be shifted correspondingly to a position, say in engagement with contact 40, as shown in the drawings, which will cause the auxiliary circuit to be connected through the segmented disk 55 and thus to be broken for 24 seconds oi? each minute, as hereinbetore described, similarly stopping,- the registration ot energy consumption in the consumers branches of the circuit for that amount oi time during; each minute, By means oi' this systen'i, the operation ot the power registering` mechanism in the consumers branches of the distribution circuit will be governed automatically by the inagnitudc of the current flowing through the main lines 1, 2, so that under full load said register will operate continuously, but will register energy consumption intermittently and in accordance with the measured load when the load is less than the maximum. Thus, when the load on the entire systeu'i changes, the switch arm 2S assumes a new position, and completes the auxiliary circuit through a different contact plate. and a differently proportioned segmented disk interrupts the auxiliary circuit, thus offering a new rate to the consumers.

While l have shown and described my improved system as ied to single phase power distribution circuits, where energy transmitted at high voltage and delivered to the consumers circuits at low potential, it will be understood that this method ot measuring energy consumption is not limited to sinfrle phase systems of power distribution, as it is equally well adapted to be used in connection with ytwo phase,` three phase or any polyphase systems ot' power distribuoir current balances ein- V nce with the number a three phase syste'n,

ploy/ed beine' ot' phas three ces are used, one in each ot s. oi" said current balances identical e systen. de

with that ol scribed, only two c two chas.A tire ancesarc rcqui sys-item su: curr ln my proposed syst .'tently the current tential coils ot the consuV possible to obtain the iliary circuit trani the a point near the place where energy is consumed. rlhe relay or sifritch with its contact element 7l can be .located near the point ot energy consu iotion. and the auxiliary cir cuit leading to any number ot con i s meters can be opened and closed by the action oi this switch. rthe switch Tl can he controlled trom some other point the dis-u tribution system by the rohr GG so that it will operate in accordance with thc measured load which controls the operation ot the current balance.

The control circuits 'for the rel 3l and the motor 2li as well as circuit for the relay 6G are all sh se rate because they operate indenendently. `However the power supplied to these coutrol circuits n'iay be derived trom one source,` though not necessarily. Power may be taken trom the lines ci the distribi on circuit to leed these control circuits. but .freue illy in power stations direct current control circuitscould be usefl with advc l fre. .any source of power can be used on any ot these control circuits, but direct current is ordinarily preferable.

lVhile l have shown and described one forni oit mechanism for making' and brealring the auxiliary circuitto the meters 'for oilierating variably and stopping' said metersA still l do not wish to limit inyselt to such construction as the same may be varied in several ways.

ln Figure 3 l have shown a modified construction of the disks 50 to showing means for varying the active periphery ot' the same. Thus. each oit' said structures com: prises two Segmente( disks 78 and 79, the disk 78 being fixed to the sha'tt while di slr 79 is mounted rotatably thereon` setscrew 80 engaging' disk 7S and passing through a slot Sl. in dick 7 affords a ready means for locking the disl: 79 in ani,Y adjusted position with respect to dislr ISL in a manner readily understood. This construction permits adjustments to be made in the timing ot the making and breakin@ ot the auxliary circuit, and consequent changes in the eli rered to 'the no- 1.7 Y is meters. 1t is curr it tor the auxdistribution wires at rate offered to the consumers for any value oli load on the main circuit.

Havingthus fully described my invention` what l claim as new and desire to secure by Letters latent, is rw l. Ii system t r lvariably 4measuring the energy consumed in electrical circuits7 comprising' a power circuit, an energy measuring andregisteringdevice in each consumers branch of the pow r circuit7 a current alance connected in the power circuit7 an auxiliary circuit derived Troni said power it. a switch in said auxiliary circuit tor controlling the operation ot the energy measuring' and registering devices.y a. plurality et contacts tor said switch, a calibrated spring' conne infr said switch with the said current balance. and

movable element ol. a motor controlled by said movable element ttor shittiirf;` said switch, said spring` operating through the shift ot said switch to brina` said movable element to neutral or equilihrium thereby stopping' said motor.

2. A system Jfor variably measuringthe electrical energy consumed in a branch ot an electrical circuit, comprising a power circuit1 a source of electrical energy for the power circuit. a branch load circuit supplied therebyT an integrating watthourmeter in the bra lch circuit. a current balance in the power circuit, an auxiliary circuit a source of electrical energy for the auxiliary circuit a switch in the auxiliary ci 1cuit comprising a switch arm. a plurality of contacts. contact fingers, and rotating switch elements for makingand breaking` the auxiliary circuit, a spring` connecting' the switch arm with the movable element ot the current balancen a. motor controlled by said movable element for shitting' said switch arm. said spring operating through the shitting` ot said switch arm to bring said movable element to .a neutral position, there by stopping said motor y and means whereby the operation ot the switch in the auxiliary circuit controls the registration oft energy consumption in the branch circuit.

3. A system tor variably measuring the energy consumed in an electrical circuit, comprising' a power circuit, aA current balance in said circuit. an auxiliary circuit derived trom said power circuit, a switch in said auxiliary circuit, a power measuring` and registering device controlled by the auxiliary circuit in each consumers branch of the power circuit, a plurality ot contacts tor said switch in the auxiliary circuit, a calihrated spring connecting' said switch with the movable element ot said current balance, a motor for shifting said switch, and a control circuit controlled by the movable element ot said current balance for controlling the direction ot rotation of said motor or for stopping the same7 said spring operating through the shift of said switch to bring said movable element to neutral or equilibrium thereby stopping said motor, a turnbuckle for adjusting the tension of the calibrated spring, a screw adjustment for changing the point of connection of the spring to the movable element, and an adjustable counter-balance tor balancing the movable element.

4. A system for variably measuring the energy consumed in an electrical circuit, comprising a source of electrical. energy, a main distribution circuit, a branch load circuit supplied thereby, an integrating watthourmeter in the branch circuit-,gy an auxiliary circuit, a source of electrical energy for the auxiliary circuit, a current balance in the main distribution circuit, a switch arm in the auxiliary circuit, means for causingthis switch arm to assume a delinite position for every value of current measured by the current balance ammeter, a plurality of contacts arranged so that the switch arm is always in electrical contact with at least one of them, electrical conductors connectingthe auxiliary circuit to each of the contacts through contact lingers, a series of segmented circular disks, means for rotating the disks continuously at a suitable uniform speed, springs for holding the contact nngers in contact with the segmented disks, stops torestrict the motion of the contact fingers s o that contact beween the contact lingers and their respective disks is broken for certain positions of the disks, and means whereby the registration ol' energy consumption in the branch circuit is controlled by the operation of the switch mechanism in the auxiliary circuit.

5. A system for variably measuring the energy consumed in a branch of an electrical circuit, comprising a power circuit, a source of electrical energy for the power circuit, a branch load circuit supplied thereby, an auxiliary circuit, asource ot electrical energy for the auxiliary circuit, an integrating watthourmeter in the branch circuit, a current balance ammeter in the main power circuit, a switch arm in the auxiliary circuit, means for causing this switch arm to assume a definite position for every7 valueof current measured by the current balance, a plurality of contacts arranged so that the switch arm is always in electrical contact With at least one of them, electrical conductors connectinn the auxiliar7 circuit to each is .l n

or the contacts through Contact nngers, a

series oi rotatable segmented circular disks,

each disk being` electrically in contact with 'ent so that the ratio of the time during which the auxiliary circuit is open or closed to the timenecessary for the disks to make one complete rotation is a variable depending upon the position of the switch arm and the load on the main power circuit, provision being made that or one position of the switch arm the auxiliary circuit may not be interrupted, and means whereby the making and breaking of the auxiliary circuit controls the registration of energy consumption in the branch of the power circuit.

6. A system kfor variably measuring the energy consumed in a branch of an electrical circuit, comprising a power circuit, a source or electrical energy, a branch load circuit supplied thereby, an integrating watthourmeter in the branch circuit, an auxiliary circuit,a source of electrical .energy for the auxiliary circuit, a switch mechanism in the auxiliary circuit, means whereby the switch mechanism in the auxiliary circuit is con-A trolled by the electrical load on the main powerl circuit, a second auxiliary circuit, a source of electrical energy for the second auxiliary circuit, a relayin the i'irst auxiliary circuit lior controlling the flow of current in the second auxiliary circuit, and means whereby the registration of energy consumption by the watthourmeter in the branch of the power circuit is controlled directly by the flow of current in the second auxiliary circuit and indirectly by the flow of current in the iirst auxiliary circuit.

In testimony whereof, l hereunto allix my signature.

PAUL H. BURKHART. 

